TWM593009U - Optical fingerprint sensing module - Google Patents

Abstract

An optical fingerprint sensing module is provided, including a substrate, an image sensor disposed on the substrate, a frame disposed on the substrate, a lens, and a plurality of micro-lenses. The micro-lenses have infrared cut-off material and are disposed above the image sensor. Light emitted from a display panel module is reflected by a finger and then sequentially propagates through the lens and the micro-lenses to reach the image sensor.

Description

Optical fingerprint sensing module

The invention relates to a fingerprint sensing module, in particular to an under-display fingerprint sensing module.

In recent years, as biometrics technologies have matured, many different biometrics can be used to identify users. Among them, since the recognition rate and accuracy of the fingerprint recognition technology are better than those of other biological features, the current application level of fingerprint recognition is wider.

The general fingerprint recognition technology mainly uses the sensing module to sense the user's fingerprint pattern, and then extracts the unique fingerprint feature in the fingerprint pattern and stores it in the memory, or directly stores the fingerprint pattern. Afterwards, when the user performs fingerprint recognition, the fingerprint sensing module will sense the fingerprint pattern and extract fingerprint features for comparison with the previously stored fingerprint features for identification, or it may be directly compared with the previously stored fingerprint features The fingerprint patterns are compared. If the two match, the user's identity can be confirmed.

First, please refer to FIGS. 1 and 2 together. FIG. 1 shows a schematic diagram of a conventional optical fingerprint sensing device, and FIG. 2 shows an enlarged cross-sectional view of part A1 in FIG. 1. The optical fingerprint sensing device shown in FIG. 1 mainly includes a display panel module D, a bottom plate B, a substrate P (such as a circuit board), a frame H, an optical lens M1, and an image sensor S And an infrared filter element F, wherein the substrate P is disposed on the base plate B, the frame H and the image sensor S are disposed on the substrate P, and the optical lens M1 is fixed in an opening of the frame H .

It should be understood that the aforementioned display panel module D includes a display element D1 and a light-transmitting element D2 disposed above the display element D1, wherein the display element D1 can emit light through the light-transmitting element D2 and illuminate the light-transmitting element D2 One finger on the element D2, then the light will reflect through the finger and pass through the display element D1 (as shown by the light L in Figure 1), and then sequentially pass through the optical lens M1 and the infrared filter element F to reach the image sense Tester S. It can be seen from FIG. 2 that the light L reaches the image sensing unit U inside the image sensor S after passing through the infrared filter element F, so as to facilitate subsequent fingerprint data storage and fingerprint identification procedures.

In the process of fingerprint sensing, the infrared light generated by the light source tends to become interference noise, which may result in poor imaging quality of the image sensor and affect the accuracy of fingerprint recognition, although Figures 1 and 2 The disclosed optical fingerprint sensing device can filter infrared light by providing an infrared filter element F to prevent infrared light from entering the image sensing unit S and affecting its imaging quality, but the conventional infrared filter element F usually uses an independent infrared light The cut-off filter sheet (infrared cut-off filter sheet), because it has a considerable thickness, is not conducive to the thinning of the optical fingerprint sensing device. On the other hand, the aforementioned infrared filter element F (optical film) usually needs to be fixed above the image sensing unit S through assembly or other processing methods, which often increases the manufacturing cost and the complexity of the assembly process.

In view of the aforementioned conventional problems, an embodiment of the present invention provides an optical fingerprint sensing module for sensing a fingerprint pattern of a finger disposed on a display panel module, including a substrate, disposed on the aforementioned An image sensor on the substrate, a frame disposed on the substrate, an optical lens, and a plurality of micro lenses. The optical lens is fixed to the frame and corresponds to a sensing area of the display panel module. The microlens has infrared cut-off material and is disposed above the image sensor. The light emitted by the display panel module is placed on the After the finger in the sensing area is reflected, it sequentially passes through the optical lens and the micro lens to reach the image sensor.

In one embodiment, no infrared filter element is provided between the optical lens and the microlens.

In one embodiment, the micro lens is formed on the image sensor by coating, spraying, or stamping.

In one embodiment, the aforementioned microlens is made of resin.

In one embodiment, the aforementioned display unit is an organic light emitting diode display unit or a thin film transistor liquid crystal display unit.

Another embodiment of the present invention provides an optical fingerprint sensing module for sensing a fingerprint pattern of a finger disposed on a display panel module, including a substrate and an image sensor disposed on the aforementioned substrate A sensor, a collimating layer disposed on the image sensor. The collimating layer has a plurality of collimating structures, wherein the collimating structure has translucency and contains infrared cut-off materials, and the light emitted by the display panel module is reflected by the fingers, passes through the collimating structure, and reaches the image Sensor.

In one embodiment, no infrared filter element is provided between the display panel module and the collimating layer.

In one embodiment, the collimating structure is formed with a plurality of collimating holes, and the collimating structure is disposed in the collimating hole.

In an embodiment, the collimating layer is an optical fiber plate, and the collimating structure has optical fiber material.

In one embodiment, the aforementioned display unit is an organic light emitting diode display unit or a thin film transistor liquid crystal display unit.

The optical fingerprint sensing module of the present invention is described below. However, it can be easily understood that the new embodiment provides many suitable new concepts and can be implemented in a wide variety of specific contexts. The specific embodiments disclosed are only used to illustrate the use of the present invention in a specific method, and are not intended to limit the scope of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in this disclosure. It is understandable that these terms, such as those defined in commonly used dictionaries, should be interpreted to have a meaning consistent with the background or context of the relevant technology and this disclosure, and not in an idealized or excessively formal manner Interpretation, unless specifically defined here.

The foregoing and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description with reference to one of the preferred embodiments of the drawings. Direction terms mentioned in the following embodiments, for example: up, down, left, right, front or back, etc., are only for directions referring to additional drawings. Therefore, the directional terms used in the embodiments are intended to illustrate rather than limit the present invention.

Please refer to FIG. 3, wherein FIG. 3 shows a schematic diagram of a micro-lens type optical fingerprint sensing device according to an embodiment of the present invention. As shown in FIG. 3, the optical fingerprint sensing device of this embodiment can be used to sense the fingerprint pattern of a finger, which mainly includes a display panel module D and an optical fingerprint sensing disposed below the display panel module D Module, the optical fingerprint sensing module mainly includes a base plate B, a substrate P, a frame H, an optical lens M1 and an image sensor S, wherein the substrate P is disposed on the base plate B, the frame H and the image sensor S are disposed on the substrate P, and the optical lens M1 is fixed in an opening of the frame H.

For example, the aforementioned image sensor S may be a charge coupled device (Charge Coupled Device, CCD) image sensor or a CMOS image sensor (CMOS Image Sensor, CIS). On the other hand, the substrate P is, for example, a flexible printed circuit board (flexible printed circuit board), and the base plate B can use a plastic or metal substrate with a higher hardness than the substrate P to provide the substrate P and The image sensor S has sufficient supporting strength.

In this embodiment, the display panel module D includes a display element D1 and a light-transmitting element D2 disposed above the display element D1, wherein the light-transmitting element D2 is, for example, a sheet glass, and the display The element D1 is, for example, an Organic Light-Emitting Diode (OLED) display element, a thin film transistor liquid crystal (TFT-LCD) display element, or a touch display (touch display) element.

It should be understood that a plurality of light-emitting units are provided inside the aforementioned display element D1, which can be used as a light source, so as to emit light through the light-transmitting element D2 and illuminate a finger placed on the light-transmitting element D2.

Please continue to refer to FIG. 3, the aforementioned frame H has a hollow structure, and an accommodating space H0 is formed therein for accommodating the aforementioned image sensor S. It can be seen from FIG. 3 that when the optical fingerprint sensing device of this embodiment is to be used for fingerprint sensing, a finger can be placed on the sensing surface D21 above the light-transmitting element D2, and the finger can be positioned on the display panel One of the modules D is in the sensing area R; Then, the light emitted by the light source inside the display element D1 will pass through the light-transmitting element D2 and reach the finger in the sensing area R, and then the light will be reflected by the finger and pass out The display element D1 (shown as light L in FIG. 3) reaches the optical lens M1, and the light can reach the image sensor S after passing through the optical lens M1.

Next, please refer to FIG. 4, wherein FIG. 4 shows an enlarged sectional view of part A2 in FIG. 3. As shown in FIG. 4, after passing through the optical lens M1, the light L will first enter a plurality of micro lenses M2 (micro lenses) on the surface of the image sensor S, and then the light L will pass through the aforementioned micro lens M2 to reach the image sensor The image sensing unit U inside the sensor S.

When the image sensor S receives the light L passing through the optical lens M1 and the microlens M2, it can convert the optical signal into an electrical signal, and the fingerprint information is contained by the aforementioned substrate P (such as a circuit board). The electrical signal is sent to a processor (not shown) for subsequent fingerprint data storage and fingerprint identification procedures.

It should be noted that the microlens M2 in this embodiment contains an infrared cut-off material (Infrared Cut-Off Material), which can effectively prevent infrared light from entering the image sensing unit U inside the image sensor S, and There is no need to additionally provide other infrared filter elements between the aforementioned optical lens M1 and the microlenses M2, which can reduce the manufacturing cost and facilitate the miniaturization of the optical fingerprint sensing device as a whole. In addition, the microlens M2 may also contain a resin material to facilitate forming and attaching to the surface of the image sensor S.

As described above, this embodiment is mainly provided by providing a microlens M2 containing an infrared cut-off material on the image sensor S to block the infrared light generated by the light source inside the display element D1 from entering the image sensor S. Therefore, it is possible to prevent noises in the optical signal from affecting the imaging quality of the image sensor S.

For example, the aforementioned microlens M2 can be formed on the surface of the image sensor S through a semiconductor process such as coating, spraying, photolithography, or etching, or imprinting. on.

In this embodiment, the aforementioned microlenses M2 may be connected to or separated from each other, and they may be arranged on the surface of the image sensor S in a matrix manner, and correspond to the image sensing unit U inside the image sensor S.

Please refer to FIG. 5 again, wherein FIG. 5 shows a schematic diagram of a collimator type optical fingerprint sensing device according to another embodiment of the present invention. It can be seen from FIG. 5 that the optical fingerprint sensing device of this embodiment can also be used to sense the fingerprint pattern of a finger, which mainly includes a display panel module D and an optical device disposed under the display panel module D Fingerprint sensing module, the aforementioned optical fingerprint sensing module mainly includes a substrate P, an image sensor S, a collimating layer C (collimating layer) and at least one optical diaphragm A, the aforementioned image sensor S It is arranged on the substrate P, the collimating layer C is arranged on the image sensor S, and the optical film A is arranged between the display panel module D and the collimating layer C.

For example, the aforementioned image sensor S may be a charge coupled device (Charge Coupled Device, CCD) image sensor or a CMOS image sensor (CMOS Image Sensor, CIS). In this embodiment, the aforementioned image sensor S and the collimating layer C can be sequentially stacked on the substrate P through a semiconductor manufacturing process, wherein a plurality of elongated collimating holes are formed inside the collimating layer C C0, and each collimating hole C0 is filled with a collimating structure C1 having translucency.

The display panel module D mainly includes a display element D1 and a transparent element D2 disposed above the display element D1, wherein the transparent element D2 is, for example, a sheet glass, and the display element D1 is, for example, a Organic light-emitting diode (Organic Light-Emitting Diode, OLED) display element, thin film transistor liquid crystal (TFT-LCD) display element, or touch display (touch display) element.

It should be understood that a plurality of light-emitting units are provided inside the aforementioned display element D1, which can be used as a light source, so as to emit light through the light-transmitting element D2 and illuminate a finger placed on the light-transmitting element D2.

Please continue to refer to FIG. 5, when you want to use the optical fingerprint sensing device of this embodiment for fingerprint sensing, you can first place your finger on the sensing surface D21 above the light-transmitting element D2; then, from the display element D1 internal light source The emitted light will pass through the light-transmitting element D2 and reach the finger, and then the light will be reflected by the finger and pass through the display element D1, and pass through the optical film A to the collimating layer C (such as the light in Figure 5) L shown). For example, the aforementioned optical film A may include a polarizing film or a pinhole layer formed with a plurality of pinholes.

After the light L passes through the aforementioned optical film A, it can be guided through the collimating structure C1 in the collimating layer C to reach the image sensing unit inside the image sensor S to avoid the light inside the collimating layer C Light cross-talk occurs with each other. It should be particularly noted that the collimating structure C1 in this embodiment contains an infrared cut-off material (Infrared Cut-Off Material), so it can effectively prevent infrared light from passing through the collimating layer C and entering the image sensor S Therefore, it is not necessary to additionally provide other infrared filter elements in the optical film A, so that the manufacturing cost can be reduced, and the overall miniaturization of the optical fingerprint sensing device can be facilitated.

For example, the collimating layer C may be a fiber optic plate (FOP), wherein the collimating structure C1 located inside the optical fiber plate is made of optical fiber material (such as glass or plastic material), and the collimating structure C1 The interior can be doped with an infrared cut-off material, which can simultaneously perform the dual functions of collimation of light and IR filtering.

It should be understood that the optical image sensor of the present invention is an under-display fingerprint image sensing device (under-display fingerprint image sensing device) whose light source may come from low illumination such as organic light emitting diode (OLED) The luminous body belongs to the low light level imaging sensor (low light level imaging sensor). For the above reasons, even a small amount of infrared light entering the image sensor S may cause considerable noise and affect the imaging quality.

In view of this, in the present invention, the micro-lens type optical fingerprint image sensing device is provided with a micro lens containing an infrared cut-off material, or by the collimator type optical fingerprint sensing device A collimating structure containing infrared cut-off material is formed inside the collimating layer, thereby eliminating the need for additional infrared cut-off filters, and can effectively prevent infrared light from entering the image sensor to improve the imaging of the image sensor Quality, thereby improving the accuracy of fingerprint identification.

Although the embodiments and advantages of the present invention have been disclosed above, it should be understood that anyone with ordinary knowledge in the technical field can make changes, substitutions, and retouching without departing from the spirit and scope of the present invention. In addition, the scope of protection of the present invention is not limited to the processes, machines, manufacturing, material composition, devices, methods, and steps in the specific embodiments described in the specification. Anyone with ordinary knowledge in the technical field can learn from the present disclosure It is understood that current or future developed processes, machines, manufacturing, material composition, devices, methods, and steps can be used according to the present invention as long as they can implement substantially the same functions or obtain substantially the same results in the embodiments described herein. Therefore, the protection scope of the present invention includes the above processes, machines, manufacturing, material composition, devices, methods and steps. In addition, each patent application scope constitutes an individual embodiment, and the protection scope of the present invention also includes a combination of each patent application scope and embodiment.

Although the new model has been disclosed above with preferred embodiments, it is not intended to limit the new model. Anyone who is familiar with this process can make some changes and retouching without departing from the spirit and scope of the new model. The scope of protection of this new model shall be subject to the scope defined in the attached patent application.

A: Optical diaphragm A1: Part B: bottom plate C: Collimation layer C0: Collimating hole C1: collimating structure D: Display panel module D1: display element D2: Light-transmitting element D21: Sensing surface F: Infrared filter element H: frame H0: accommodation space L: light M1: optical lens M2: micro lens P: substrate R: Sensing area S: Image sensor U: image sensing unit

FIG. 1 shows a schematic diagram of a conventional optical fingerprint sensing device. FIG. 2 shows an enlarged cross-sectional view of part A1 in FIG. 1. FIG. 3 shows a schematic diagram of an optical fingerprint sensing device according to an embodiment of the invention. Figure 4 shows an enlarged cross-sectional view of part A2 in Figure 3. FIG. 5 shows a schematic diagram of an optical fingerprint sensing device according to another embodiment of the invention.

A1: Part

B: bottom plate

D: Display panel module

D1: display element

D2: Light-transmitting element

D21: Sensing surface

H: frame

H0: accommodation space

L: light

M1: optical lens

P: substrate

R: Sensing area

S: Image sensor

Claims (10)

An optical fingerprint sensing module for sensing a fingerprint pattern of a finger arranged on a display panel module, including: A substrate An image sensor arranged on the substrate; A frame set on the substrate; An optical lens fixed to the frame and corresponding to a sensing area of the display panel module; and A plurality of micro-lenses with infrared cut-off material and arranged above the image sensor, wherein the light emitted by the display panel module is reflected by the finger placed in the sensing area and then passes through the optical lens in sequence And the microlenses to reach the image sensor. The optical fingerprint sensing module as described in item 1 of the patent application scope, wherein no infrared filter element is provided between the optical lens and the microlenses. The optical fingerprint sensing module as described in item 1 of the patent scope, wherein the microlenses are formed on the image sensor by means of coating, spraying or imprinting. The optical fingerprint sensing module as described in item 1 of the patent application scope, wherein the microlenses are made of resin. The optical fingerprint sensing module as described in item 1 of the patent application scope, wherein the display panel module is an organic light emitting diode display panel module or a thin film transistor liquid crystal display panel module. An optical fingerprint sensing module for sensing a fingerprint pattern of a finger arranged on a display panel module, including: A substrate An image sensor arranged on the substrate; A collimating layer is arranged on the image sensor and has a plurality of collimating structures, wherein the collimating structures contain infrared cut-off materials, and the light emitted by the display panel module passes through the fingers after being reflected These collimating structures reach the image sensor. The optical fingerprint sensing module as described in item 6 of the patent application scope, wherein no infrared filter element is provided between the display panel module and the collimating layer. The optical fingerprint sensing module as described in item 6 of the patent application scope, wherein the collimating layer is formed with a plurality of collimating holes, and the collimating structures are disposed in the collimating holes. The optical fingerprint sensing module as described in item 6 of the patent application scope, wherein the collimating layer is an optical fiber board, and the collimating structures have optical fiber materials. The optical fingerprint sensing module as described in item 6 of the patent application range, wherein the display panel module is an organic light emitting diode display panel module or a thin film transistor liquid crystal display panel module.

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